Timepiece



June 6, 1933. R. NELS N 1,912,650

TIMEPIECE Filed March 3, 1950 IN VEN TOR. ANTa/v Fr. NELGO/V.

A TTORNEYS.

Patented June 6, 1933 UNITED STATES ANTON B. NELSON, OF BUBLINGAME, CALIFORNIA rmnrmcr.

lppllcatlon filed March 3', 1930. Serial No. 432,790.

The present invention relates to improvements in time pieces and more particularly to electrically operated time pieces and its principal object is to provide means in connection with an electrically operated time piece for insuring continuous operation of the same during a temporary break down of the electrical circuit.

More particularly it'is proposed in the present invention to provide in combination with an electrically operated time piece an auxiliary mechanical actuating means which automatically enters into action when the electric,-

cal operating means fails.

A further object of the present invention is to provide a simple device that may be constructed at little expense for carrying out the above idea.

Further objects and advantages of my invent-ion will appear as the specification proceeds.

The preferred form of my invent-ion is illustrated in the accompanying drawing in which Figure 1 shows a horizontal section through a time. piece made in accordance with my invention,

\ Figure 2 a vertical section taken along line 22 of Figure 1, and projected from the latter figure, and

Figure 3 a section taken I Figure 1.

Vhile I have shown only the preferred form of my invention, I wish to have it ur 9r- 5 stood that various changes or'modifications may be made within the scope of the claims hereto attached withoutdeparting from the spirit of the invention.

Referring to the drawing'in detail, it will be noted that a suitable housing 1 is provided with a conventional dial 2 over which the minute hand 3 and the hour hand 4 are adapt-- ed to move. The minute hand is fastened to a central shaft 5 suitably supported in a bracket 6 and a central plate 7. and this shaft has the spider 8 of a differential transmission fastened thereto. the transmission comprising two ring gears 9 and 10. and a plurality of radial pinions 11 with which the ring gears o engage on opposite sides. The shaft 5 drives along line 33 of the hour hand through a conventional train of reducing gears indicated'at- 12 and a sleeve 13.

The ring gear 9 is connected to a convenshortshaft :20 supported. in an arm 21 of the bracket 6 previously referred to.

. For operating the ring gear 10 I use a conventional mechanical clock mechanism including a main spring 22 confined in the housing 23 a gear 24 actuated by the spring, a train of reducing gears shown at 25, 26. and 27 respectively, an escapement wheel 28. a pallet fork 29 and a balance wheel 30. The pivot 31 on which the gear 26 is mounted has a pinion 321thereon, which latter meshes with the ring gear 10.

The mechanical clock mechanism is normally locked in inactive position by means of. an armature 33 pivoted to the housing 16 as at 34. which is normally attracted by the electro-magnet 14. This armature has a finger 35 projecting into the path of the pins 36 extending from the balance wheel. whereby the entire mechanical clock mechanism is locked as long as" the electro-magnet is active. 'hen for some reason the current ceases to flow in the circuitof the electro-magnet, the

armature 33 is drawn away from the same by a spring 37 whereby the balance wheel is released and the mechanical actuating mechanism becomes active.

In operating the reducing gears confined within the housing 16 are arranged to revolve the pinion 17 at the rate of one revolution per minute. and this speed is further reduced 32 being made to rotate at the rate of eight revolutions per hour, the ring gear 10 at the rate of two revolutions per hour, and the spider at the rate of one revolution per hour.

The operation of my invention will be readily understood from the foregoing description. As long as the electrical system is in operation, the mechanical actuating means is locked in inactive position by the engagement of the finger 35 with the balance wheel 30. This also locks the lower ring gear 10 againstrotation while at the same time rotary motion is imparted to the upper ring gear 9 by the motor through the train of gears in the housing 16, and through the pinion 17. the gear wheel 18 and the pinion 19. The upper ring gear 9 transmits its motion. at half speed to the spider 8 which is fastened on the shaft 5 and operates the minute hand. while the hour hand is 0perated at the same time through the train of gears 12.

If for some reason the electrical actuating means becomes inactive as by the blowing out of a fuse, the armature 33 is drawn away from the electro-magnet 14 by the spring 37, whereby the mechanical actuating mechanism is released for acting on the lower ring gear 10.

At this time theupper ring gear 9 is held against rotation by the resistance ofl'ered by the train of gears connecting the same to the motor. The lower ring gear 10 now transmits motion to the spider at the rate of one revolution per hour. which motion is transmitted to the minute and hour hands in the manner previously described.

I claim:

1. In a time piece of the character described. a shaft having time indicating means thereon. a spider on the shaft having radial pinions thereon. two ring gears mounted for engagement with the pinions from opposite sides. a mechanical actuating means connected to one of the ring gears and having means for normally. locking the same against movement and an electrical actuating means operative on the other ring gear having means associated therewith for releasing the mechanical actuating means when the electrical actuating means becomes inactive.

2. In a time piece of the character described. a shaft having time indicating means thereon. a spider on the shaft having radial pinions thereon. two ring gears moilnted for engagementwith the pinions from opposite sides. a mechanical actuating means connected to one of the ring gears an electrical actuating means operative on the other ring and means for rendering one of the actuating means inactive while the other is active.

3. In a timing device including a time indicating means, a constant speed electric driving means. an auxiliary driving means means for regulating said auxiliary drivin means, a common driven means connected ANTON R. NELSON. 7g 

